42215 Mods Improvements Alternative builds And Attachments

[Ngoc Nguyen]

Let's start the PF conversion.

 

[Ngoc Nguyen]

Plenty of space for 4 L motors + 1 battery box + 2 IR receivers after the original gearbox is removed.

[Ngoc Nguyen]

The PF RC Conversion mod is finished.

 

https://reb.li/m/231183

 

[mpj]

Have you tested it in real life to check everything works fine? What is the speed of the arm?

[Glaysche]

I started with an RC PoweredUp mod.  I think I have something pretty good for the tracks and rotation.

 

 

 

I haven't started on converting the top functions yet.  The motors and hub are pretty well hidden when in this position.  When the top rotates, it becomes more visible.

The lower section is very height constrained.  I ended up with the support for the gears on the bottom being 2L lower than the rest of the chassis, reducing ground clearance.  It might be possible to put those gears inside but that would require much more major changes to the structure.  I might revisit after converting the top functions.

[Saruzeufel]

On 8/6/2025 at 10:34 PM, SNIPE said:

1.PTO1 (e.g. drill rotation)

2.PTO2 (e.g. drill hammering)

3.attachment latch/unlatch

I'm really looking forward to your progress on this, please keep us updated with what you come up for the quick coupler. I tried building one with those 3 functions a while ago but it ended up being way to big and bulky, so I am really interested ins seeing your approach

[SNIPE]

15 hours ago, Saruzeufel said:

I'm really looking forward to your progress on this, please keep us updated with what you come up for the quick coupler. I tried building one with those 3 functions a while ago but it ended up being way to big and bulky, so I am really interested ins seeing your approach

I'll try, but I have a tendency to half finish things

[Ngoc Nguyen]

After quite a number of trials and errors I finally found a gear combination that strikes an acceptable balance between playability and speed.

The biggest bottleneck is determining the speed for the base XL LAs. They can definitely be geared to move faster, and I did try some gearing combos that make them move faster, but past a certain point they struggle to lift the arm with an empty bucket. Since the movements of all 3 stages are too slow to actually play digging, I instead optimize the speed that at least permit a tool swap play. 

Video and instruction for 42215 Playability Mod coming soon.

Edited September 4 by Ngoc Nguyen

[Ngoc Nguyen]

42215 Playability Mod video:

 

This mod improves the playability of 42215. It is meant to make 42215 playable right from the box, so there's no major redesign, and the use of new parts is kept to the minimum.

Changes in this mod are as follows.

- A second switch: This allows quicker and easier control of the functions. Instead of having to slide one switch along a distance of 9 studs, the player can slide each switch along a distance of 3 studs only. It is not meant to allow two functions to run simultaneously, since the motor doesn't have enough power.

- Improved speed: The new gear combo allows the arm to move at decent speed to mimic the digging function. However, since an increase in speed results in a decrease in torque, the bucket can't carry much weight, so actual digging isn't really suitable. However, it is possible to do tool swapping play.

Instruction: https://reb.li/m/234388

[Ngoc Nguyen]

On 8/2/2025 at 3:03 AM, Zerobricks said:

Quickly looking at the instructions, it shuld be possible to center the battery box and add another motor. This would allow faster gearing ratio and perhaps ability to control 2 functions at once.

I managed to add another motor and hard couple two motors together. The sad news is that their performance is only slightly better than that of one single motor. Video is coming soon. This set is truly unfixable.

Edited September 11 by Ngoc Nguyen

[Bartybum]

7 hours ago, Ngoc Nguyen said:

I managed to add another motor and hard couple two motors together. The sad news is that their performance is only slightly better than that of one single motor. Video is coming soon. This set is truly unfixable.

Uh oh... looking forward to it

[SNIPE]

one possibility might be to replace the bevel gears with just a 12 tooth single bevel gear, but then we do something I've never seen before, that is: use just the red 28 tooth idler gears  then have another  single tooth bevel gear on the other side. Its kinda big to fit in though but you can put half beams inside of the 28 tooth idler gear at least.

I also have every spike prime motor (x1L,x4M and x6 small) + other lego motors so l can test stuff out if needed. sadly no buwizz 3.0 , only 2.0

[Ngoc Nguyen]

Here's playability mod v1, with 1 motor and modified gear ratio to make it run faster.

 

Here's playability mod v2, with 2 motors, and slightly slower gear ratio. You'd think that means more power right? At least that's what I thought. The result is rather disappointing, as the hard coupled motors still occasionally to lift the arm with the bucket. They struggled even more to lift the arm with the breaker.